Studies have been made on the muscarinic receptor, and it is known that compounds having muscarinic receptor antagonistic activities cause bronchodilation, suppression of gastrointestinal motility, suppression of acid secretion, dry mouth, mydriasis, suppression of bladder contraction, hypohidrosis, tachycardia, or the like. It is known that the muscarinic receptor includes at least three subtypes. The M.sub.1 receptor mainly exists in the brain or the like, the M.sub.2 receptor in the heart or the like, and the M.sub.3 receptor in the smooth muscles or gland tissues.
A number of such compounds having muscarinic receptor antagonistic activities are hitherto known and, for example, atropine is a typical example ("The MERCK INDEX, ELEVENTH EDITION", p. 138). However, atropine antagonizes the M.sub.1, M.sub.2 and M.sub.3 receptors non-selectively, so that it is difficult to use it for the treatment of a specific disease. In recent years, according to the progress of the studies on the subtypes of the muscarinic receptor, compounds having selective antagonistic activities against the M.sub.1, M.sub.2 or M.sub.3 receptor have been investigated (an unexamined published British Patent Application No. 2,249,093, an unexamined published Japanese Patent Application (kokai) 1-131145, and an unexamined published Japanese Patent Application (kokai) 3-133980). There is a demand for a compound having selective antagonistic activity against muscarinic M.sub.3 receptor among these three subtypes and is free from the cardiac side effects resulting from the M.sub.2 receptor.
The compound represented by the following general formula is described in an unexamined published Japanese Patent Application (kokai) 62-252764. ##STR2## (wherein L represents NH or O; X and Y each independently represents a hydrogen atom or a C.sub.1-6 alkyl group or they may be combined together to form a bond;
R.sub.1 and R.sub.2 each independently represents a hydrogen atom, a C.sub.1-6 alkyl group . . . (omission) . . . ; PA1 R.sub.3 and R.sub.4 each independently represents a hydrogen atom, a halogen atom, CF.sub.3, a C.sub.1-6 alkyl group . . . (omission) . . . , a phenyl group, an amino group which may optionally be N-substituted by one or two groups selected from phenyl, C.sub.1-6 alkyl groups or may optionally be N-disubstituted by C.sub.6-8 polyethylene . . . (omission) . . . ; ##STR3## p is 1 or 2; and q is 1-3. PA1 X: a single bond or a methylene group; PA1 R: a halogen atom, a hydroxyl group, a lower alkoxy group, a carboxyl group, a lower alkoxycarbonyl group, a lower acyl group, a mercapto group, a lower alkylthio group, a sulfonyl group, a lower alkylsulfonyl group, a sulfinyl group, a lower alkylsulfinyl group, a sulfonamido group, a lower alkanesulfonamido group, a carbamoyl group, a thiocarbamoyl group, a mono- or di-lower alkylcarbamoyl group, a nitro group, a cyano group, an amino group, a mono- or di-lower alkylamino group, a methylenedioxy group, an ethylenedioxy group or a lower alkyl group which may be substituted by a halogen atom, a hydroxyl group, a lower alkoxy group, an amino group or a mono- or di-lower alkylamino group; PA1 l: 0 or 1, PA1 m: 0 or an integer of 1 to 3, and PA1 n: an integer of 1 or 2, hereinafter the same apply similarly) PA1 quinuclidine derivatives wherein R represents a halogen atom, a lower alkyl group, a hydroxyl group, a lower alkoxy group, a nitro group, a cyano group, an amino group or a mono- or di-lower alkylamino group, and the ring A represents an aryl group, a cycloalkyl group, a cycloalkenyl group, a 5- or 6-membered monocyclic heteroaryl group having 1 to 4 hetero atoms selected from the group consisting of an oxygen atom, a nitrogen atom and a sulfur atom or a 5- to 7-membered saturated heterocyclic group, in which such a ring may be substituted by a halogen atom, a lower alkyl group, a hydroxyl group, a lower alkoxy group, a nitro group, a cyano group, an amino group or a mono- or di-lower alkylamino group, and their salts, or quaternary ammonium salts; PA1 quinuclidine derivatives wherein m is 0, and the ring A represents an aryl group, a cycloalkyl group or a cycloalkenyl group which may be substituted by a halogen atom, a lower alkyl group, a hydroxyl group or a lower alkoxy group, or a 5- or 6-membered monocyclic heteroaryl group having 1 to 4 hetero atoms selected from the group consisting of an oxygen atom, a nitrogen atom and a sulfur atom, and their salts, or quaternary ammonium salts; PA1 quinuclidine derivatives wherein the ring A represents a phenyl group which may be substituted by a halogen atom or a lower alkyl group, a cycloalkyl group, a pyridyl group, a furyl group or a thienyl group, and their salts, or quaternary ammonium salts; PA1 quinuclidine derivatives wherein X represents a single bond, and their salts, or quaternary ammonium salts; and PA1 quinuclidine derivatives wherein n is 2, and their salts, or quaternary ammonium salts.
The compound described in the above patent literature is disclosed as a 5-HT antagonist and no disclosure about the muscarinic receptor antagonistic activity is found. The above compound is clearly distinguished from the compound according to the present invention in pharmacological effects.